Crystal Growth Promotion and Defect Passivation by Hydrothermal and Selenized Deposition for Substrate-Structured Antimony Selenosulfide Solar Cells.

Antimony sulfide-selenide (Sb(S,Se)) is a promising light-harvesting material for stable and high-efficiency thin-film photovoltaics (PV) because of its excellent light-harvesting capability, abundant elemental storage, and excellent stability. This study aimed to expand the application of Sb(S,Se) solar cells with a substrate structure as a flexible or tandem device. The use of a hydrothermal method accompanied by a postselenization process for the deposition of Sb(S,Se) film based on the solar cell substrate structure was first demonstrated. The mechanism of postselenization treatment on crystal growth promotion of the Sb(S,Se) film and the defect passivation of the Sb(S,Se) solar cell were revealed through different characterization methods. The crystallinity and the carrier transport property of the Sb(S,Se) film improved, and both the interface defect density of the Sb(S,Se)/CdS interface and the bulk defect density of the Sb(S,Se) absorber decreased. Through these above-mentioned processes, the transport and collection of electronics can be improved, and the defect recombination loss can be reduced. By using postselenization treatment to optimize the absorber layer, Sb(S,Se) solar cells with the configuration SLG/Mo/Sb(S,Se)/CdS/ITO/Ag achieved an efficiency of 4.05%. This work can provide valuable information for the further development and improvement of Sb(S,Se) solar cells.